After the “experimental turn” (Overdevest et al. 2010) in the social sciences, a growing body of literature on inter- and transdisciplinary research methods with laboratory character evolved. Urban Transition Labs (Nevens et al. 2013), Urban Living Labs (Marvin et al. 2018) or Real-world Laboratories (Wanner et al. 2018) use interventions and experimental approaches as core research modes. Their aim is to produce transformative knowledge to initiate social change, trough co-design and co-production of knowledge between academia, civil society actors and local political or administrative authorities. The lab approaches have a lot in common with participatory and action research methods, especially due to their focus on normative change through collaborative production of knowledge. This Session wants to address the question how transdisciplinary research methods and in particular interventions and experiments can help to further develop participatory and action research methods? We welcome theoretical and empirical papers, which connect participatory and action research with transdisciplinary research methods, in particular lab approaches like Urban Transition Labs, Real-world Laboratories or Urban Living Labs.